Speaker



FIG. 1 is a perspective view of a speaker as seen from the front, top, and side;

FIG. 2 is a top view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a back view thereof;

FIG. 6 is a side view thereof; and,

FIG. 7 is an opposite side view thereof.

The dotted line portions of the drawings represent environmental structure only and form no part of the claimed design. 

The ornamental design for a speaker, substantially as shown and described. 